diff --git a/DependencyInjection/MarkdownExtension.php b/DependencyInjection/MarkdownExtension.php
index bc36654..76abc01 100644
--- a/DependencyInjection/MarkdownExtension.php
+++ b/DependencyInjection/MarkdownExtension.php
@@ -13,6 +13,11 @@ class MarkdownExtension extends Extension
     {
         $loader = new XmlFileLoader($container, __DIR__.'/../Resources/config');
         $loader->load('parser.xml');
+        
+        if(isset($config['class']))
+        {
+            $container->setParameter('markdown.parser.class', $config['class']);
+        }
     }
 
     public function helperLoad($config, ContainerBuilder $container)
diff --git a/README.markdown b/README.markdown
index 1d32955..67ee901 100644
--- a/README.markdown
+++ b/README.markdown
@@ -14,6 +14,11 @@ Optionnally enable the twig markdown filter :
     twig.config: ~          # Enable Twig
     markdown.twig: ~        # Enable the markdown filter
 
+You can also define your own Parser class :
+
+    markdown.parser:
+        class: Bundle\HelloBundle\MarkdownParser
+
 ## USAGE
 
     // Use the service